Telephone-receiver.



J. NOBLE, DEGD. 0. w. GHAKBEBLAIN, ADIINISTRATOE.

TELEPHONE RECEIVER.

APPLICATION FILED JAN. 11, 1908.

953,970. Patented Apr. 5, 1910.

UNITED s'ra'ins PATENT ()FFICE.

JAY NOBLE, OF ST. LOUIS, MISSOURI, ASSIGNOR OF ONE-HALF 'IO CHARLES W. CHAM- BERLAIN, 01F ST. LOUIS, MISSOURI; CHARLES W. CHAMBERLAIN ADMINISTRATOR OF SAID NGBLE, DECEASED.

TELEPHONE-RECEIVER.

To all whom it may concern:

Be itv known that 1, .lm' NOBLE, a citizen otthe United States. and resident of Qt Louis, Missouri, have invented certain new telephone receivers, and relates to the construction of a diaphragm employed in such receivers.

In the drawings l igure l is a plan view of a telephone receiver. having its upper end. shown in mid section and the diaphragm shown in diametric mid section. Fig. 2 is a top plan .view of thc...diaphragn of my in;

vention.

As shown in the drawings, the diaphragm of my invention comprises a circular iron disk 3 upon which are superii'nposed a series of other circular iron disks 4, 5, 6, and 7, respectively; said other disks being of decreasing diameters and being superimposed and mounted upon the first-named disk and upon each other in the order of their decreasing diameter. The said disks are then united together by means of the rivet 8 or other suitable connecting means.

In the form illustrated in F i, the diaphragm of my invention is shown in place in a receiver 9 containing' the electro-magnet commonly used in the art, having the polepieces 10, the receiver being provided with the cap 11 having the central. perforation l2.

Specification of Letters Patent.

Application. filed January 11, 1808.

Yatented- Apr. 5, 1910.

Serial No. 410,435.

By the construction described and shown I have provided a diaphragm pyramidal in form, presenting to the pole-piece or pole: pieces of the bar-magnet wherewlth 1t co-v acts a relatively substantial metallic mass, whose superior etlieienoy in use I attribute to an enhanced electromotive force caused by the greater excitation of the magnet created by increasing the bulk of metal in the diaphragm. But this theory I advance tentatively. The merit of my improved diaphragm has been shown in practice to reside in the accurate reproduction and transmission of sound both as to pitch, volume and quality.

Having y Eihdhnyi lcmiong lntao I claim as new and c esire tohave secured to me by the grant of Letters Patent, is:

The improvement in telephone receivers comprising a diaphragm composedof a circular iron disk and one or more other circular iron disks of lesser and decreasing diamctcrs superimposed and mounted upon the first-named disk and upon each other inthe order of their decreasing diameters, substantially as described.

In testimony whereof, I have signed my name to this specification, in presence of two subscribing witnesses.

JAY NOBLE.

Witnesses CHARLES KSPICKLES', JAMES L. Hominvs. 

